Wildlife contraceptives of various kinds are under development. Contraceptives such as these are intended to control population growth

Population growth

Population growth is the change in a population over time, and can be quantified as the change in the number of individuals of any species in a population using "per unit time" for measurement....

 among both tame and wild animals

Wildlife

Wildlife includes all non-domesticated plants, animals and other organisms. Domesticating wild plant and animal species for human benefit has occurred many times all over the planet, and has a major impact on the environment, both positive and negative....

.

White-tailed deer

White-tailed Deer

The white-tailed deer , also known as the Virginia deer or simply as the whitetail, is a medium-sized deer native to the United States , Canada, Mexico, Central America, and South America as far south as Peru...

 may be controlled with contraceptives in suburb

Suburb

The word suburb mostly refers to a residential area, either existing as part of a city or as a separate residential community within commuting distance of a city . Some suburbs have a degree of administrative autonomy, and most have lower population density than inner city neighborhoods...

an areas, where they are sometimes a nuisance

Nuisance

Nuisance is a common law tort. It means that which causes offence, annoyance, trouble or injury. A nuisance can be either public or private. A public nuisance was defined by English scholar Sir J. F...

. In parts of the United States, does are shot with darts containing a contraceptive vaccine

Vaccine

A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins...

, rendering them temporarily infertile. The Humane Society of the United States

Humane Society of the United States

The Humane Society of the United States , based in Washington, D.C., is the largest animal advocacy organization in the world. In 2009, HSUS reported assets of over US$160 million....

 runs a deer birth control program, but it is experimental; it may not be cost-effective in the long run. It may cost $300 to $1000 per deer.

The vaccine used is porcine zona pellucida

Porcine zona pellucida

Porcine zona pellucida is a form of zona pellucida extracted from the ovaries of pigs, often referred to by the initials PZP.The zona pellucida is a thick membrane that surrounds the unfertilized eggs of mammals. In order for an egg to be fertilized, sperm must first bind to, and then penetrate the...

 (PZP), or derivatives. This form of immunocontraception

Immunocontraception

Immunocontraception is a birth control method that uses the body's immune response to prevent pregnancy.-In humans:Experiments are undergoing to test the effectiveness of an immunocontraceptive vaccine that inhibits the fusing of spermatozoa to the zona pellucida. This vaccine is currently being...

 prevents sperm from accessing an ovum

Ovum

An ovum is a haploid female reproductive cell or gamete. Both animals and embryophytes have ova. The term ovule is used for the young ovum of an animal, as well as the plant structure that carries the female gametophyte and egg cell and develops into a seed after fertilization...

. Another form of deer contraception, called GonaCon, produces antibodies to sex drive hormones

Sex steroid

Sex steroids, also known as gonadal steroids, are steroid hormones that interact with vertebrate androgen or estrogen receptors. Their effects are mediated by slow genomic mechanisms through nuclear receptors as well as by fast nongenomic mechanisms through membrane-associated receptors and...

 in the deer, causing them to lose interest in mating.

Similar forms of injectable contraceptive for is being studied for use in elk

Elk

The Elk is the large deer, also called Cervus canadensis or wapiti, of North America and eastern Asia.Elk may also refer to:Other antlered mammals:...

 and gray squirrel

Gray squirrel

Gray squirrel or grey squirrel may refer to several species of squirrel indigenous to North America:*The Eastern gray squirrel , from the eastern United States and southeastern Canada; introduced into Britain, Ireland, western North America, Italy, and South Africa;*The Western Gray Squirrel , from...

s.

Oral contraceptives may also be developed for population control among a variety of animals, including deer

Deer

Deer are the ruminant mammals forming the family Cervidae. Species in the Cervidae family include white-tailed deer, elk, moose, red deer, reindeer, fallow deer, roe deer and chital. Male deer of all species and female reindeer grow and shed new antlers each year...

, feral pigs, coyote

Coyote

The coyote , also known as the American jackal or the prairie wolf, is a species of canine found throughout North and Central America, ranging from Panama in the south, north through Mexico, the United States and Canada...

s, cougars, dog

Dog

The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...

s and cat

Cat

The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...

s.

Pigeons

Feral Pigeon

Feral pigeons , also called city doves, flying rats, city pigeons or street pigeons, are derived from domestic pigeons that have returned to the wild. The domestic pigeon was originally bred from the wild Rock Pigeon, which naturally inhabits sea-cliffs and mountains. All three types readily...

 have been a target for experimental contraceptives for decades. An oral contraceptive is in use for the control of Canada Geese

Canada Goose

The Canada Goose is a wild goose belonging to the genus Branta, which is native to arctic and temperate regions of North America, having a black head and neck, white patches on the face, and a brownish-gray body....

.